Screw-joint fastener for drill-rods, &amp;c.



UNITED STATES PATENT OFFICE.

FRANK wULFF, oFV coLUsA, CALIFORNIA.

SPECIFICATION forming part of Letters Patent No. 694,514, dated March 4, 1902. Application led September 4, 1901. Serial No. 74,328. (No model.)

To a/ZZ whom, t may concern:

Be it known that I, FRANK WULFF, a citizen of the United States, residing at Colusa, in the county of Colusa and State of California, have invented certain new and useful Improvements in Screw-Joint Fasten ers for Drill-Rods and the Like, of which'the following is a specification. v

My invention relates to an improved screwjoint fastener for drill-rods and the like, the object of my invention being to provide an improved device whereby the drill-bit may be more securely attached to the drill-rod than has hitherto been the case.

In drilling oil-wells great loss is occasionally experienced by the dropping of the drill-v bit from the rod and support. Oftenti-mes it is impossible to recover thel drill-bit by fishing, as it is called, so that the well has to be abandoned,with the loss of the labor and time of months.

The object of my invention is to provide a device by which'the drill-bit may be more securely fastened to the drill-rod or whereby two sections of drill-rods may be more securely fastened to'each other than has heretofore been the case. The invention is, however, also applicable to other fastenings, and I do not desire to limit my invention to the 1application of the same to-drill-rods or drillits. l

My invention therefore resides in the novel construction, combination, and arrangement of parts for the above ends hereinafter fully speciied, and particularly pointed out in the claims.

In the accompanying drawings, Figure 1 is a side elevation of my improved screw-joint fastener. Fig. 2 is a vertical section of the same, the wedge being shown as inserted in the upper slot. Fig. 3 is a side elevation of the lower section of the joint detached. Fig.

4 is a side elevation of the expanding-pin detached. Fig. 5 is a top plan View of the lower section ofthe joint, and Fig. 6 is a section on the line A A of Fig. 2.

Referring to the drawing, 1 represents the upper section, and 2 the lower section, of the screw-joint. The upper section 1 is formed at its lower end with a socket 3, flaring from about the center outwardly, as shown at 4, and slightly flaring from the same point Ain- ,4 'of the socket.

wardly, as shown at 5, and the lower section has a head 6, tapering in itslower portion 7 and cylindrical in its upper or outer portion 8. The cylindrical portion 8 of the head is adapted to enter the inner end of the socket, while the tapering portion 7 is screw-threaded and is screwed into the iiaringonter portion The head is formed with slits 9, extending longitudinally thereof from the upper end and at right angles'to each other, thus permitting said head to expand under suitable pressure. When so expanded,

4if in position in the socket, the headwill bind tightly in the slightly-flaring inner end of the vsocket and will prevent the lower section from unscrewing from the upper section. v.In order y to produce said expansion,th ere is provided an expanding-pin 10, inserted in central longitudinal holes in the head and in the upper section labove the socket, the ends of said expandingpin extending into upper and lower transverse slots 11 12. The pin 10 is formed with a tapering or conical surface 13, which engages a conical seat 14 in the upper end of the head, and thus when said pin 10 is pressed down said head is caused to expand, thereby binding the parts together, as already described. The pin 10 may be thus driven down to bind the parts by driving transversely through the upper slot 11 a suitable wedge 15, thereby forcing the upper end of the pin downward, and, conversely, the pin 10 may be driven upward by driving said wedge 15 through the lower slot 12.

By the'above construction there is provided a screw-joint fastening which is perfectly securel against separationof the parts and which doesunot materially weaken the strength of the parts or necessitate any protuberances which Awould interfere with the movement of the drill-bit.

I claim- 1. In a screw-joint fastening, the combination of a section having a socket converging or tapering inwardly at its outer portion and also screw-threaded thereat and Haring or diverging inwardly at its inner portion, a second section having a head converging or tapering outwardly at its inner portion and also screw-threaded thereat to engage the screwthreaded portion of the socket, said head also having an outer portion expansible into an ICO outwardly-flaring form to lit snugly and bind within the inner portion of the socket, and means for so expanding the outer portion of said head after the head is screwed into the socket, substantially as described.

2. In a screw-joint fastening, the combination of a section having a socket converging or tapering inwardly at its outer portion and also screwthreaded thereat and Haring or dverging inwardly at its inner portion, a second section having a head converging or tapering outwardly at its inner portion and also screw-threaded thereat to engage the screwthreaded portion of the socket, said head also having an outer portion expansible into an outwardly-daring form to bind Within the daring inner portion of the socket, the two sections having an axial aperture running DeSSeS.

FRANK WULFF. Witnesses:

FRANCIS M. WRIGHT, CECELIA POWNING. 

